Question

Find the range and the first and third quartiles for the data set.82, 63, 65, 71, 81, 20, 45

Answer 1

We want to find the range, first quartile and third quartile of the data set

82, 63, 65, 71, 81, 20, 45

First we arrange the numbers in ascending order from smallest to biggest. This is

20, 45, 63, 65, 71, 81, 82

Range. This is largest number minus smallest number.

So the range is

`\begin{gathered} 82-20 \\ =62 \end{gathered}`

The First quartile. First we have to lacate the meddian. The meddian is the middle number, which is 65.

To get the first quartile, we look at the number before 65, which is 63

Then we check at the middle number between 63 and the first number which is 20.

Hence the first quartile is 45

The third quartile. We look at the middle number between 71 and 82, which is the last number. This middle number is 81.

Hence, the third quartile is 81.

Therefore our answer is

Range = 62

First quartile = 45

Third quartile = 81

The 3rd option is the correct answer